Some stats first:
Porsche 911 Turbo - $111K (base price)
Rear Engine/AWD
3.6 Liter TT Flat 6
415HP/415lbs of TQ
6 spd manual
3395 lbs
0-60 mph 3.6 seconds
Quarter mile 11.9 seconds
Lateral G's 0.96
13.0 inch brakes (all around)
BMW M3 (E46) - $45K (base price)
Front Engine/Rear Wheel Drive
3.2 Liter Inline 6
333HP/246lbs of TQ
6 spd manual
3458 lbs
0-60 mph 4.7 seconds
Quarter mile 13.6
Lateral G's 0.91
12.8 inch brakes (front)
12.9 inch brakes (rear)
True that the 911T has become a less involved car, but it's truly the most driver friendly supercar out there for the money most likely. The way it behaves, adjusts & corrects is remarkable. It may not challenge a person as much as say a M3...but it is by no means a slouch when it comes to handling.
The M3 has always had superb handling and awesome steering. This new M3 is by no means less of an M3 from the last that enchanted us so very much. But it does not hang w/the 911T in terms of overall speed...so it must rely on it's handling to keep pace.
My verdict: I'd rather say...I am going to go get my Porsche (I choose the Porsche...I like to speed on the highway past other lowly cars)